SoundID Sound ID 300 Guide De Démarrage Rapide page 7

Choose a PersonalSound ™ Level
You can customize your listening experience when on a call by choosing
one of three PersonalSound ™ levels. Use the Volume/PersonalSound ™
Program Button to cycle through the three available enhancement levels.
To cycle to the next level, hold the button down for approximately two
seconds until you hear a corresponding beep (one, two, or three beeps
for normal, medium, or strong enhancement). Your headset is set to
"normal" by default.
There is a fourth setting, indicated by four beeps, that turns off
all sound enhancement and noise reduction. This setting can be used
to demonstrate the noise reduction capabilities of the Sound ID 300.
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